When I set out to write this section of the review, I realized many of my initial attempts to describe the sound of the Liquid Lightning came out sounding like Zen riddles, as in, “What is the sound of one hand clapping?” Nevertheless, let me make an attempt at the task.
What is the sound of the Liquid Lightning? In one sense it is essentially no sound at all, by which I mean to say that the Cavalli is as free from colorations, distortions, and moments of transient excess, ringing, or overshoot as any headphone amp I’ve yet heard. In other words, it reproduces music without injecting much if any sonic personality of its own into the proceedings. In another sense, though, the sound of the Cavalli is very much the sound of the recordings and source components with which it is fed, with nothing added and nothing taken away. In my experience, it seemed that no detail or sonic nuance—no matter how small—could escape detection by the Liquid Lightning; the amp just finds whatever’s there and reproduces it cleanly without fuss, bother, or histrionics.
The Cavalli has positive qualities in abundance: dead neutral frequency response, ultra low levels of background noise, terrific transient speed, stunning resolution of low level details, and powerful and expressive dynamics. But the amp is more than the sum of these qualities, because what it really brings to the party is an effortless and unforced quality of sonic honesty—as if it has sworn to tell the truth and nothing but the truth. As the motto engraved on the wall of the CIA headquarters put things in a passage drawn from the Gospel according to St. John, “...ye shall know the truth and the truth shall make you free.” Or at least that’s the theory.
When coupled with the Stax SR-009 the Liquid Lightning offers listeners an extraordinarily precise and detailed view of the inner workings of recordings—a view so accurate and revealing that you quickly find yourself becoming a discerning connoisseur of the finer aspects of recording and mixing techniques. With the Stax/Cavalli combo on the case, it becomes child’s play to draw subtle qualitative distinctions between tracks on an album, or even to spot ultra-subtle qualitative variations between passages within an individual track. If, down deep, you’ve always dreamed of hearing all of the music, the Stax/Cavalli combo may well be the state of the art package to make those dreams come true.
There is, as so often is the case with such things, an upside and a downside to the Cavalli’s capabilities. The upside is that more or less everything you could ever want to know about a recording is laid bare before you. The downside is that sometimes great music winds up being captured in highly imperfect recordings where hearing the flaws that are present (and in explicit detail) can leave you feeling less than blessed (or perhaps simply overwhelmed with more information than you can readily process). Either way, the Cavalli just keeps on telling you the truth, no matter what.
Are there drawbacks? Well, one small drawback is that the Cavalli needs about 200 hours of run-in time during which time the amp will, as Cavalli product documentation points out, “continue to improve with regard to bass impact, more open sound, warmth, and ‘sweetness’…” Our listening tests confirmed this. When first heard before adequate playing time has been accumulated, the amp can initially sound a little sterile and mechanical. But give it time; the longer you play it, the better it sounds.
Next, the amp does—for each listening session—need a fair bit of warm up before it is truly ready to sing. Cavalli recommends a minimum of 15-30 minutes of warm up time, but I found an hour or more made it sound even better. When cold, the amp is playable but again sounds a bit thin and edgy before it is fully warmed up.
How does the Cavalli compare against the two other world-class electrostatic headphone amps we’ve recently reviewed? I would say the Cavalli is fully the equal of the Woo WES with upgraded tubes in terms of clarity, definition, and dynamics, but with two important differences. When you listen to the Woo WES, you are always conscious of it delivering a finely resolved, ultra high-definition sound, but you may also wonder whether the Woo could be—in an almost subliminal way—achieving perceived definition by subtly overemphasizing the leading edges of transient sounds. By comparison, the Cavalli is no less finely resolved or well defined, yet it does not give an underlying sense of overemphasis; instead, details unfold in a natural way that is almost self-effacing in its honesty and directness. Second, as my colleague Tom Martin noted in his Woo WES review, the WES can at times sound “somewhat stressed or shouty on vocals,” which, Tom felt, “suggests a frequency response elevation in the midrange.” In contrast the Cavalli has no such hints of midrange elevation so that it generally sounds smooth (assuming the recording itself is smooth) yet very, very focused.